We plan to further characterize intestinal cells in terms of their membrane structure with special emphasis on the distribution and biogenesis of specific membrane proteins and their changes with cell differentiation. The hybridoma technique will be used to prepare and characterize monoclonal antibodies against membrane proteins and enzymes using isolated membranes derived from brush border and basolateral membranes from both villus and crypt cells. We will extensively use our newly described intestinal epithelial cell line to examine cell differentiation and factors affecting differentiation in tissue culture. We will study the biosynthesis of membrane factors and glycoprteins in crypt and villus cells using radioactive sugar and amino acid precursors in vivo. We will also attempt to determine whether the monoclonal antibody technique can be useful in identifying carrier proteins of the brush border and to test for their ability to influence sugar and amino acid transport using the membrane vesicle technique.